A couple seconds of digging finds motherboards that cost an average of $300. Assuming you (unfortunately) _have_ to support whatever it is you're supporting...
- Socket 478 (P4/Celeron), 2GB max, RS422/485, MiniPCI, $???: https://adek.com/product/MB-800V
- Socket 478, 2GB max, $???: https://www.bressner.co.uk/products/motherboards/mb-g4v620-b...
- Socket 478, 6xUSB2, $???: http://vegashine.sell.everychina.com/p-104455439/showimage.h...
- Socket 478, 2GB max, CF, 6xUSB2, $???: http://vegashine.sell.everychina.com/p-104455440-4-pci-3-isa...
- LGA775 (Core 2 Quad), 4GB max, 1xPCIx16, M-SATA, 2xLAN, IrDA, 5xRS232, $320: https://www.ebay.com/itm/283550673178
- LGA775, 6xRS232, 8xUSB2.0, CF, RS422/485, $179: https://www.aliexpress.com/item/32892452763.html
- LGA775 (Intel G41), 4GB max, DVI, 4xSATA 3G, 2xLAN, 8xRS232, (does not support ISA bus mastering), $???: http://vegashine.sell.everychina.com/p-104455435/showimage.h...
All of the above have 3xISA, at least one RS232 and at least one LPT.
